URINARY SYSTEM AP URINARY SYSTEM AKA EXCRETORY SYSTEM

URINARY SYSTEM A&P

URINARY SYSTEM • AKA EXCRETORY SYSTEM • REMOVES WASTES & EXCESS WATER • MAINTAIN ACID-BASE BALANCE • HELPS MAINTAIN BODY’S HOMEOSTASIS

URINARY SYSTEM PARTS OF THE URINARY SYSTEM: Ø 2 KIDNEYS Ø 2 URETERS Ø 1 BLADDER Ø 1 URETHRA

KIDNEYS • BEAN-SHAPED ORGANS • FOUND ON EITHER SIDE OF VERTEBRAL COLUMN • LOCATED IN RETROPERITONEAL SPACE • RETROPERITONEAL SPACE=AREA BEHIND SPACE UPPER PART OF ABD CAVITY; SEPARATED FROM ABD CAVITY BY PERITONEAL MEMBRANE

KIDNEYS • PROTECTED BY RIBS & FAT CUSHION • HELD IN PLACE BY CONNECTIVE TISSUE • EACH KIDNEY IS ENCLOSED IN MASS OF FATTY TISSUE=ADIPOSE CAPSULE • EACH KIDNEY IS COVERED BY A TOUGH, FIBROUS TISSUE=RENAL FASCIA OR FIBROUS CAPSULE

KIDNEYS DIVIDED INTO 2 MAIN SECTIONS: CORTEX & MEDULLA ØCORTEX= CORTEX o. OUTER SECTION o. CONTAINS MOST OF THE NEPHRONS (NEPHRONS AID IN PRODUCTION OF URINE)

KIDNEYS ØMEDULLA= MEDULLA o. INNER SECTION o. CONTAINS MOST OF THE COLLECTING TUBULES (COLLECTING TUBULES CARRY URINE FROM NEPHRONS THROUGH THE KIDNEY)

KIDNEYS • EACH KIDNEY HAS A HILUM • HILUM=NOTCHED OR INDENTED AREA HILUM • THE URETER, NERVES, BLOOD VESSELS, & LYMPH VESSELS ENTER & LEAVE THE KIDNEY THROUGH THE HILUM

KIDNEYS • NEPHRONS=MICROSCOPIC FILTERING UNITS NEPHRONS OF THE KIDNEY • THERE ARE MORE THAN 1 MILLION NEPHRONS PER KIDNEY

KIDNEYS EACH NEPHRON CONSISTS OF A: ØGLOMERULUS ØBOWMAN’S CAPSULE ØPROXIMAL CONVOLUTED TUBULE ØDISTAL CONVOLUTED TUBULE ØCOLLECTING DUCT (TUBULE)

KIDNEYS • THE RENAL ARTERY CARRIES BLOOD TO THE KIDNEY • BRANCHES OF THE RENAL ARTERY PASS THROUGH THE MEDULLA TO THE CORTEX • THIS IS WHERE BLOOD ENTERS THE 1 ST PART OF THE NEPHRON, THE GLOMERULUS • GLOMERULUS=CLUSTER OF CAPILLARIES GLOMERULUS

KIDNEYS • WATER, MINERAL SALTS, GLUCOSE, METABOLIC PRODUCTS, & OTHER SUBSTANCES ARE FILTERED OUT OF THE BLOOD AS IT PASSES THROUGH THE GLOMERULUS • RBCS & PROTEINS ARE NOT FILTERED OUT

KIDNEYS • FILTERED BLOOD LEAVES THE GLOMERULUS & MOVES TO THE RENAL VEIN WHICH CARRIES IT AWAY FROM THE KIDNEY • THE SUBSTANCES FILTERED OUT BY THE GLOMERULUS ENTER THE NEXT SECTION OF THE NEPHRON, BOWMAN’S CAPSULE

KIDNEYS • BOWMAN’S CAPSULE=C-SHAPED STRUCTURE CAPSULE THAT SURROUNDS THE GLOMERULUS • IT IS THE START OF THE CONVOLUTED TUBULE • BOWMAN’S CAPSULE PICKS UP THE FILTERED MATERIALS & PASSES THEM INTO THE CONVOLUTED TUBULE

KIDNEYS • AS THE FILTERED MATERIAL PASSES THROUGH THE TUBULE, TUBULE SUBSTANCES NEEDED BY THE BODY ARE REABSORBED AND RETURNED TO THE BLOOD CAPILLARIES • THOSE SUBSTANCES ARE MOST OF THE WATER, GLUCOSE, VITAMINS, AND MINERAL SALTS

KIDNEYS • EXCESS GLUCOSE AND MINERAL SALTS, SOME WATER, AND WASTES (UREA, URIC ACID, AND CREATININE) REMAIN IN THE TUBULE • THESE EXCESS SUBSTANCES ARE A CONCENTRATED LIQUID=URINE

KIDNEYS • URINE ENTERS COLLECTING DUCTS (TUBULES) LOCATED IN THE MEDULLA • THE COLLECTING DUCTS EMPTY INTO THE RENAL PELVIS (RENAL BASIN), • RENAL PELVIS=FUNNEL-SHAPED STRUCTURE PELVIS THAT IS THE 1 ST SECTION OF THE URETER

URETERS • 2 MUSCULAR TUBES • 10 -12 INCHES LONG • RENAL PELVIS=FUNNEL-SHAPED 1 ST SECTION PELVIS OF URETER • ONE URETER EXTENDS FROM THE RENAL PELVIS OF EACH KIDNEY TO THE BLADDER

URETERS • PERISTALSIS MOVES URINE THROUGH URETER FROM KIDNEY TO BLADDER

BLADDER • HOLLOW, MUSCULAR SAC • FOUND BEHIND SYMPHYSIS PUBIS • LOCATED AT MIDLINE OF PELVIC CAVITY • RECEIVES URINE FROM URETERS • STORES URINE UNTIL IT IS VOIDED • VOID= VOID URINATE= URINATE MICTURATE

BLADDER • LINED WITH MUCOUS MEMBRANE • MUCOUS MEMBRANE HAS RUGAE (FOLDS) • RUGAE DISAPPEAR AS BLADDER EXPANDS TO FILL WITH URINE • BLADDER WALLS ARE MADE OF TRIPLE LAYER OF VISCERAL (SMOOTH) MUSCLE

BLADDER • CIRCULAR SPHINCTER MUSCLE CONTROLS THE BLADDER OPENING TO PREVENT EMPTYING • RECEPTORS IN BLADDER SEND OUT A REFLEX ACTION WHICH OPENS THE MUSCLE • URGE TO VOID OCCURS WHEN BLADDER HAS 250 ML BUT IT CAN HOLD MUCH MORE

BLADDER • INFANTS CANNOT CONTROL THE REFLEX ACTION • AS CHILDREN GROW, THEY LEARN TO CONTROL THE REFLEX

URETHRA • TUBE THAT CARRIES URINE FROM BLADDER TO OUTSIDE OF BODY • URINARY MEATUS=EXTERNAL OPENING OF MEATUS URETHRA

URETHRA FEMALE URETHRA: Ø 1. 5 INCHES LONG ØOPENS IN FRONT OF VAGINA ØCARRIES ONLY URINE

URETHRA MALE URETHRA: Ø 8 INCHES LONG ØPASSES THROUGH THE PROSTATE GLAND ØEXISTS THE PENIS ØCARRIES BOTH URINE & SEMEN (NOT AT THE SAME TIME)

URINE • LIQUID WASTE PRODUCT OF URINARY SYSTEM • APROX 95% WATER • CONTAINS DISSOLVED WASTE PRODUCTS: UREA, URIC ACID, CREATININE, MINERAL SALTS, PIGMENTS

URINE • EXCESS USEFUL PRODUCTS (LIKE SUGAR) CAN ALSO BE FOUND IN URINE • WHEN USEFUL PRODUCTS ARE IN URINE, IT USUALLY INDICATES DISEASE

URINE • KIDNEYS FILTER ABOUT 150 QUARTS OF LIQUID DAILY • ABOUT 1, 500 -2, 000 ML (1. 5 -2 QUARTS) OF URINE ARE PRODUCED DAILY

URINATION TERMS USED TO DESCRIBE CONDITIONS THAT AFFECT URINATION: ØPOLYURIA=EXCESSIVE URINATION ØOLIGURIA=BELOW NORMAL AMOUNT OF URINE ØANURIA=ABSENCE OF URINATION ØHEMATURA=BLOOD IN URINE

URINATION TERMS ØPYURIA=PUS IN URINE ØNOCTURIA=URINATION AT NIGHT ØDYSURIA=PAINFUL URINATION ØRETENTION=INABILITY TO EMPTY BLADDER ØINCONTINENCE=INVOLUNTARY URINATION

URINATION TERMS ØPROTEINURA=PROTEIN IN URINE ØALBUMINURA=ALBUMIN (A BLOOD PROTEIN) IN URINE